fostek



(No Model.) 3 Sheets-Sheet 2'.

M. A. FOSTER.

FUENAQE.

Patented June 17 884.

Aides 'NITED STATES PATENT Erica.

'MIOHAEL A. FOSTER, OF ST. LOUIS, MISSOURI.

FURNACE.

SPECIFICATION forming part of Letters Patent No. 300,703, dated June 17, 1884. Application filed September 29, 1883. (No modcLl To all whom it may concern:

Be it known that I, MIoHAEL A. Fosrnn, of the city of St. Louis, in the State of Missouri, have invented certain new and useful Improvements in Furnaces, of which the following is a full, clear, and exact description, reference being had to the accompanying drawings, forming part of this specification.

Reference is made to the claims for statement of invention.

Figure 1 is a side elevation showing my improvement applied to a steam-boiler furnace, and I shall throughout describe my improvement in this connection. Fig. 2 is an enlarged detail showing the injector in axial section and its connections in side elevation. Fig. 3 is one-half in front View (the breeching being removed) and one-half in transverse section at 3 3, Fig. 8. Fig. 4 is a transverse vertical section at 4. 4, Fig. 8. Fig. 5 is a transverse vertical section at 5 5, Fig. 8, with the crownarch removed. Fig. 6 is a transverse vertical section at 6 6, Fig. 8, with the crown-arch removed. Fig. 7 is a perspective View of a grate-bar section. Fig. 8 is a longitudinal vertical section at 8 8, Fig. 9. Fig. 9 is a longitudinal horizontal section at 9 9, Fig. 8. Fig. 10 is a perspective View of a furnace-door, and Fig. 11 is a vertical section of the same.

The steam-boiler setting is shown at A and the boiler at B. O is the fire-front, and D the door, of the furnace. E is the fire-grate, and F the fire-chamber. The sides of the firechamber are made with slant walls G, pro- 3 5 jecting into the fire-chamber toward the grate,

from which springs an arch, H, that spans the fire from side to side, and which extends the whole length of the-grate-bars, as shown. .The rear edge of the arch is made concave, and the bridge-wall I is made with a beveled part, I, in proximity to the top of the arch, 'so as to leave there a passage for the products of combustion between the rear edge of the arch and the bridge-wall. (See Figs. 8 and 9.) The arch has also apertures H, for the upward passage of products of combustion from the fire-chamber to the boiler. The fire may have 'supply of air in the usual manner from the I ing-coils.

the ash-pit, and having a side opening, IE at top, discharging the air horizontally over the fire, (beneath the arch but I do not limit myself to such means for supplying air at the front of the fire, merely preferring to use such an arrangement. G are passages extending vertically and inwardly through the slant walls from the ash-pit into the fire-chamber.

J is a secondary bridge-wall, and K is apit between thetwo bridge-walls, containing heat- A part of the products of combustion passes over the bridge-walls, as shown by arrows in Fig. 8, while a part of the gases passes through descending passages I, extending through the bridge-wall I to the bottom of the pit K, from which they may pass upward and over the top of the second bridge-wall, J; or they may pass across the bottom of the pit K and through a passage, J, in the second bridgewall, J. This passage may be closed or partly closed by a sliding damper, L, worked by a rod extending through the side wall of the setting A.

M is an air-pipe extending from the outside of the side wall of setting A transversely through the bridge-wall I, at the upper side of the passages I. The pipe is perforated or part out out at these passages, (see Fig. 8,) so that air from the outside enters these passages, to mix with the products of combustion passing through them.

N is a horizontal pipe closed at the ends, and having numerous small holes in its sides for the escape of jets of air into the pit-K. The pipe N is supplied with airby an upright pipe or pipes, N, connected with its middle, and receiving air by a horizontal pipe or pipes, N extending from the ash-pit, (see Fig. 8,) or from the outside, (see Fig. 6,) or both. The pit K alsocontains two double coils of pipe, one for superheating steam,which will be first described, and the second for imparting additional heat to the gases resulting from the mixture of the superheated steam with oil or atmospheric air, or both, or to the steam alone.

0 is a pipe extending from the steam-space of the boiler to the double coil of pipe I? within the pit K. The last end of the coil 1? is connected by an elbow, P, with the horizontal pipe Q, (see Fig. 1,) and the pipe Q is steam injector.

with the receiving and discharging ends of a (See Figs. 1 and 2.) The pipe R. has a valve or cock, R and the pipe R has a check-valve, R preventing the retrograde movement of the gasesfrom the pipe Q to the injector.

Q is avalve in the pipe Qbetween thepipe R and R.

S is an air-pipe, supplied with a valve, S.

T is a pipe in connection with a supply of coal-oil or other oil, and having a valve, T, by which the supply may be cut off. The pipe T is in connection with the receivingnozzle V of the injector. Uis the conical nozzle of the injector. These nozzles may have any suitable size and form. The pipe Q connects by means of an elbow, Q", with one end of the coil-pipe W within the pit K, so that the matters from the injector pass through this coil W and become very highly heated and put into a condition for rapid combustion as soon as they come in contact with the flame beneath the boiler. The injector-nozzles are inclosed by a case, X, into which air from the pipe S enters when the valve S is open. The pipecoil W is connected by apipe, Y, (see Figs. 9

. and 1,) with a transverse pipe, Z, that extends over the secondbridge-wall, J, and has numerous small perforations for the escape of the highly-heated gases, which mix with the products of combustion from the furnace and cause the combustion of any inflammable matter therein. A single transverse pipe, Z, is shown; but there may be more than one, or a single pipe formed with return bend or bends and extensions from side to side of the furnace. The pipe Y is shown extended at Y for the connection of other perforate pipes Z.

a a are transverse partitions extending across the side flues between the boiler and the sidewalls of the setting. These partitions are over the second bridge-wall, J, and serve to detain any smoke that may be passing along these flues and cause it to descend in proximity to the jet-pipe Z, for the combustion of inflammable matter; I

b b are pipes whose ends are open to the outer air above the top of the setting A, and which descend through the side flues, their lower ends being open and discharging immediately above the bridge-wall I. The sides of the pipes b are perforated, so as to enable the inward passage of smoke to mix with the air that is descending the pipe, and thus the mixture of air and smoke will be carried down upon the flame over the bridge-wall I.

b are dampers, by which the upper ends of the pipes b may be partly or wholly closed.

The furnace-door is made with an air-nozzle', D, through which the outer air enters the fire-space when the dooris closed. (See Figs. 10 and 11.) This nozzle is flattenedvertically and expanded horizontally at the inner end, D, which is near the level of the top of the fire, so that the entering air is spread laterallyover the fire to cause an equal combustion. The door is formed of an inner and an outer plate connected by a flange at'top, bottom, and sides, with openings D at the corners for the circulation of air between the plates.

C is a door in the setting, by which access may be had to a pit, c, in the bottom of the combustion-chamber.

. K is a door opening to bottom of pit K.

I claim as my invention- 1. In a furnace, the combination, with a firechamber, grate, and ash-pit, of the slant walls G, projecting into the fire-chamber toward the grate, having vertical and inwardly-projecting air-passages extending from the ash-pit to the fire-chamber, and an arch, H, which springs from the slant walls contiguous to and over the exits of the air-passages, as shown and described.

2. The bridge-wall I, having descending openings 1, and the air-pipe M, in communication with the outer air and with the passages I, substantially as set forth.

3. The combination, with the bridge-wall I, having passages I, and the perforate air-pipe N, located at the rear of the bridge-wall and supplying air alike to the products-of. com- 'bustion passing over and through the bridgewall.

4. The two bridge-walls 'I and J, with pit K between them, and provided with passages I and J, in combination with the perforate airpipe N.

5. A furnace having a pit, K, at the rear of the bridge-wall I when the bridge-wall has passages leading to the lower part of the pit and the pit contains a superheating steamcoil in communication with the steam-space of the boiler.

6. The combination, in a furnace, of a pit, K, a steam-coil, 1?, within the pit, an injector receiving steam from the coil, and with a perforate pipe or pipes, Z, within the combustionchamber of the furnace.

7. The combination of two superheatingcoils, P and W, in pit K, and an injector interposed between them to produce circulation therein, and pipe Z, as set forth.

8. The combination of two superheatingcoils, P and W, within the combustion-chamber of a furnace, an injector interposed between'the coils, an air-supply pipe, S, in communication with the injector, and a pipe, Y, conveying the heated gases from the coil to the combustion-chamber of the furnace or other destination.

9. The combination of coils P and W, inj ector U V X, air-pipe S, conducting-pipe Y, and perforate pipe Z, discharging into the combustion-chamber of the furnace.

10. The combination, with a furnace, of the pipe 12, perforated its whole length beneath the setting or top, open at top to the outer air, and extending down between the boiler and the side wall of the setting A to the neighborhood of the fire, adapted to carry smoke down with the air, substantially as and for the pur pose set forth.

11. The combination, with the ordinary or any suitable boiler-setting, A, the boiler, and

a bridge-wall, of a second bridge-wall, J ,and a wall, a, built across the side flues between 5 the boiler and setting, forming a part of the second bridge-wall,and extending part of the distance toward the bottom of the boiler, leaving an opening for the passage of the heated current, the boiler forming part of the top of 10 the passage, substantially as shown and described. v

12. The combination, in a boiler-furnace, of

the air-supplying devices D, E, G, b, and N,

the perforate arch II,bridge-walls I and J,witl1 passages I J through them, the superheating- 15 coils P and W between the bridge-walls, the injector U V X, and connecting-pipes and valves, substantially as set forth.

13. The combination,with the superheatingcoils PW, supply-pipe O, and discharge-pipe 2o Y, of the injector U V X, connecting-pipes Q R B, and valves Q, R, and R substantially as set forth.

MICHAEL A. FOSTER.

Witnesses:

SAML. KNIGHT, GEO. H. KNIGHT. 

